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Workhorse Thermostat

36 items

Upgrade your vehicle's thermostat with A-Premium's high-quality options. Choose reliability and durability for a smoother ride.

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Thermostat Housing for 2004-2005 Workhorse FasTrack FT1601Thermostat Housing for 2004-2005 Workhorse FasTrack FT1601
A-Premium®Part # APTHA0198
Thermostat Housing for 2004-2005 Workhorse FasTrack FT1601
4.798 Reviews
$22.99
Low stock: Only 5 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse FasTrack FT1601: 2004 2005
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ColorNatural
ConditionNew
item #10152L8D
Show less
Thermostat Housing for 2007-2011 Workhorse W62
A-Premium®Part # APTHA0198
Thermostat Housing for 2007-2011 Workhorse W62
4.798 Reviews
$22.99
Low stock: Only 5 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse W62: 2007 2008 2009 2010 2011
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ColorNatural
ConditionNew
item #10152E3U
Show less
Engine Coolant Thermostat for 2004-2005 2007-2009 2011 Workhorse Custom Chassis W24
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2004-2005 2007-2009 2011 Workhorse Custom Chassis W24
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse Custom Chassis W24: 2004 2005 2007 2008 2009 2011
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H52T
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Thermostat Housing for 2006-2011 Workhorse W42
A-Premium®Part # APTHA0198
Thermostat Housing for 2006-2011 Workhorse W42
4.798 Reviews
$22.99
Low stock: Only 5 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse W42: 2006 2007 2008 2009 2010 2011
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ColorNatural
ConditionNew
item #10152HZX
Show less
Engine Coolant Thermostat for 2006-2010 Workhorse Custom Chassis W18
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2006-2010 Workhorse Custom Chassis W18
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse Custom Chassis W18: 2006 2007 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H278
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 2002-2005 Workhorse Custom Chassis W52
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2002-2005 Workhorse Custom Chassis W52
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse Custom Chassis W52: 2002 2003 2004 2005
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H4AE
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 2006-2009 Workhorse W18
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2006-2009 Workhorse W18
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse W18: 2006 2007 2008 2009
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H42H
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 2006-2009 Workhorse W16
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2006-2009 Workhorse W16
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse W16: 2006 2007 2008 2009
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H1YV
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 2001-2009 Workhorse W22
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2001-2009 Workhorse W22
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse W22: 2001 2002 2003 2004 2005 2006 2007 2008 2009
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H587
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 2007-2009 Workhorse W21
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2007-2009 Workhorse W21
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse W21: 2007 2008 2009
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H42X
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 1999-2005 Workhorse P42
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 1999-2005 Workhorse P42
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H3N4
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 2005-2009 Workhorse W25
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2005-2009 Workhorse W25
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse W25: 2005 2006 2007 2008 2009
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H13L
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 2001-2009 Workhorse W20
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2001-2009 Workhorse W20
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse W20: 2001 2002 2003 2004 2005 2006 2007 2008 2009
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H1X7
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 1999-2005 Workhorse P32
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 1999-2005 Workhorse P32
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H2T9
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 2007-2009 Workhorse R26
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2007-2009 Workhorse R26
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse R26: 2007 2008 2009
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H4Z9
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Engine Coolant Thermostat for 2004-2009 Workhorse W24
A-Premium®Part # APTHE082
Engine Coolant Thermostat for 2004-2009 Workhorse W24
4.798 Reviews
$20.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Workhorse W24: 2004 2005 2006 2007 2008 2009
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Workhorse
Item LocatedUnited States
Quantity1
ConditionNew
item #1014H1RK
Note
【Note-1】 Start to Open Temperature: 91℃.
【Note-2】 This item comes with seal.
Show less
Page 2 of 2

What is an engine thermostat?

 While all engines can become too hot, if your thermostat isn't working correctly, your engine's well-being is at serious risk. The engine thermostat, often simply referred to as a thermostat, regulates the engine's operating temperature within an optimal range (typically around 195 to 220 degrees Fahrenheit).

How does a car thermostat work?

As a temperature-sensitive valve within the cooling system, a car thermostat responds to changes in coolant temperature. Understanding how it works by the following breakdown steps:

  • Closed position (cold start)

Initially closed to help the engine warm up quickly.

  • Heating up

The engine generates heat during operation.

  • Opening the thermostat

A temperature-sensitive element (usually wax) causes the thermostat to open gradually.

  • Coolant flow

When open, coolant flows from the engine to the radiator.

  • Maintaining optimal temperature

Adjusts coolant flow to maintain the ideal engine temperature.

  • Temperature regulation

Continuously adjusts to prevent overheating and ensure efficient operation.

Signs of a bad thermostat

  1. Overheating: The engine becomes excessively hot due to a stuck-closed thermostat.
  2. Low or fluctuating temperature: A thermostat stuck open results in a cooler engine, affecting fuel efficiency and heating.
  3. Temperature warning light: Illuminates to indicate engine overheating due to a faulty thermostat.
  4. Poor fuel efficiency: Stuck-open thermostat reduces fuel efficiency as the engine operates less efficiently at lower temperatures.
  5. Inadequate cabin heating: Insufficient cabin heating in cold weather with a thermostat that's stuck open.
  6. Coolant leaks: Gasket or sealing issues can lead to coolant leaks.
  7. Rapid temperature fluctuations: The gauge shows rapid swings between hot and cold.
  8. Engine running hot at idle: Higher engine temperature during idle or in traffic due to restricted coolant flow.
  9. Slow or inconsistent warm-up: Longer-than-normal warm-up times, even in moderate weather.
  10. Inconsistent heater operation: This affects the performance of the vehicle's heater, causing inconsistent or inadequate heating in cold weather.

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Jul 29, 2026